1. Field of the Invention
This invention relates to a method and device for changing motor oil, and, optionally, flushing the motor oil reservoir and crankcase components in internal combustion engines of all sizes. Such internal combustion engines can be found on automobiles, trucks, tractors, heavy earth moving equipment, military equipment, stationary equipment or the like. More particularly, this invention relates to processes in which residual spent oil and other contaminants retained and adhering to the surfaces of the internal engine lube oil flow channels of the engine components such as the crankshaft, bearings, connecting rods, filter, oil cooler, etc. of the internal combustion engine are expediently removed. This invention also relates to a device and method for removing the retained spent motor oil in the lube oil flow channel/channels and replacing it with a suitable amount of fresh motor oil in an integrated self-contained process at high speeds with almost no exposure to oil vapors of the spent fresh engine oil.
2. Background of the Relevant Art
The benefits of routine oil changes to internal combustion engines are well known. Routine engine or lube oil changes have been shown to increase engine life and performance. With repeated prolonged use, motor oil builds up metallic and non-metallic suspended particles from the abrasive and or the adhesive wear of engine parts against one another and from products of incomplete combustion and improper air intake. The particles, in turn, cause abrasive wear of the engine bearings, piston rings and other moving parts and result in the reduction of the motor oil lubricity as various additives and lubricating components become depleted. This adversely effects engine performance and, if left unchanged, can destroy or cripple the engine performance.
It is recommended by at least one oil manufacturer that total solid concentration be limited to levels below 3.0% with levels of silica being present in amounts lower than 25 ppm and sodium in amounts lower than 200 ppm.
To obtain satisfactory automotive engine performance, and maintain solid concentration levels in the motor oil lower than the recommended 3.0%, changing the motor oil in an automobile engine is a necessary, but an undesirable, dirty, and time-consuming task. As vehicles are presently designed, the oil pan serves the purpose of a reservoir for circulation of engine oil. Engine oil is drawn from the oil pan where it is pumped under pressure through internal oil distribution passages drilled in the engine block, crank shaft, connecting rods, bearings, etc. The oil exits the internal oil distribution passages through various carefully positioned openings to lubricate the reciprocating and rotating parts of the engine. The motor oil then drains back to the oil pan for recirculation through the automobile oil filter as well as any oil cooler units present in larger vehicles such as large trucks and back into the lube oil passages. To prolong oil usefulness, the oil is passed through an oil filter mounted on the engine. For example in passenger cars the filter may be mounted at the bottom of the engine block. Once the oil becomes contaminated, the spent oil must be changed to prolong engine life. At such oil changes, it is also recommended that the oil filter also be replaced. For higher compression engines, to increase gas mileage, frequent oil changes become even more important.
In the conventional oil change process the drain plug, located in the lowermost region of the oil pan, is opened. The degraded (spent) oil containing suspended particles is permitted to flow under gravity out of the pan into a suitable receptacle. After the spent oil is removed, the used oil filter can be removed and replaced. The drain plug can, then, be replaced and fresh oil added to the engine; usually through a separate opening, such as in the engine valve cover. During the process the oil filter is unscrewed and replaced.
The process of gravity drainage does not remove all of the spent oil with its metallic and non-metallic particulates which is retained in oil flow channel components because gravity drainage provides only minimum scrub cleaning or scouring action and cannot dislodge strongly adhering particulates and degraded oil components. A significant portion sticks to the oil pan walls, and to the surfaces and passages of engine oil flow components such as the crank shaft, connecting rods, pistons engine block, cylinder head and the like. Another portion remains as residual oil in the oil filter, engine lines, and oil cooler coils. This creates two problems. First degraded oil components and particles remain to be mixed with fresh motor oil. The concentration of contaminants is lowered by dilution but only a part of the total contaminants are eliminated. Thus the engine is never exposed to truly fresh oil in a completely clean engine environment. Second, a portion of spent oil remains in the oil filter. This amount can constitute up to 20% of the total oil present in the engine. When it remains in the oil filter, this retained oil is removed when the oil filter is replaced. Even more important is the fact that the oil contained in the old filter cannot be efficiently recycled or reclaimed. This poses environmental hazards and wastes a valuable recyclable resource.
Conventional oil change processes are essentially the same whether performed at home, at service stations or in rapid oil change centers which have opened in various recent years. Spent or dirty oil is allowed to collect in the oil pan and is, then, permitted to drain from the oil pan through the drain plug opening located in the lowermost portion of the oil pan. The drain plug opening is, then, closed and fresh oil is added to the crankcase and oil pan through a suitable opening such as the valve cover. Used oil filters with their burden of spent oil are discarded and new empty oil filters are inserted in their place.
In this basic procedure, the oil pan and crankcase never drain completely. Oil containing suspended, gelatinous, and sticky particles remains on the walls of the pan and the surfaces of the crankcase components, and in the various oil distribution passages, to mix with the fresh oil added during the conventional oil change process and subsequent engine use. This reduces the life of the oil filter which, in turn, further reduces the life of the engine itself over an extended period of time.
The oil change process in the so-called quick oil change or ten-minute oil change centers is faster than that performed by other automotive service centers simply because the focus of the total service business is directed to oil changes only. Quick oil change centers are more efficient simply because they are organized to be so. The rate of oil drainage and oil fill rates are the same as those of service stations because of the constant drainage and filling force limited by gravity. Also, the process employed in these oil change centers does not clean the crankcase components any better than other conventional oil change processes. Thus, while in stations and rapid oil change centers, the process can be simplified with the use of hydraulic racks, special oil collection receptacles and the like, the basic procedure of drainage through a restricted drain opening, removal of the oil-laden oil filter, replacement with a empty filter finally, oil replacement is standard and as is gravity.
This basic procedure has several drawbacks. It is time-consuming. The speed with which the oil drains through the drain plug opening is limited by that restrictive opening and by gravity. In commercial settings, this can detain personnel and valuable, expensive resources such as hydraulic racks while waiting for the oil to drain. As previously indicated, the oil pan never drains completely. Oil containing suspended and sticky particles adheres to the walls of the pan to be mixed with the new oil added. This reduces the life of the oil filter which further reduces the life of the engine itself over extended use for a period of years.
The basic process is also messy and exposes the operator to undesirable oil vapors. The drained oil must be moved, handled and, ultimately, disposed of in an appropriate manner. Drainage into open containers increases opportunities for spillage and mishandling and exposure. Fresh oil introduced into the opening in the engine valve cover can be accidentally spilled in the engine compartment. The spilled oil can smoke and burn if spilled on the manifold and can attract dirt and grime, regardless.
Many processes and devices have been proposed to remove residual oil and contaminants from the oil pan and/or crankcase components. U.S. Pat. No. 2,554,389 to Stevens discloses a crankcase cleaning apparatus which has a non-retractable spray wand which is adapted to extend into the oil pan through the drain plug opening and be fixed relative thereto. An unspecified cleaning fluid is sprayed under pressure through the wand to contact the interior surfaces of the oil pan and limited portions of the crankcase to dislodge any residual contaminants. The fluid and dislodged contaminants are allowed to drain out through the drain plug opening and are collected in a liquid receiver situated on the exterior of the oil pan for collection and eventual reuse. The fixed wand in this device does not permit efficient and complete cleaning of the interior lube passages of the lube oil components. Additionally, the manner in which the cleaning fluid is collected brings with it an elevated risk of spillage.
U.S. Pat. No. 3,489,245 to Broadwell discloses an apparatus for flushing oil pans of internal combustion engines after the spent oil has been removed from the pan. Flushing fluid can be introduced into the oil pan and crankcase through a spray nozzle which is mounted in the drain plug opening. The device disclosed in Broadwell does not permit introduced cleaning fluid to thoroughly contact the interior surfaces and passages of the lube oil flow components and the oil pan and dislodge adhering solid and oil contaminants and oil. The spray nozzle apparatus disclosed in the Broadwell reference includes a complex recirculating system to pump and process the sprayed cleaning fluid. This system can never completely remove all residual oil and cleaning fluid which accumulates in the bottom of the oil pan opening and nozzle assembly. Furthermore the system cannot be used to accomplish an oil change.
U.S. Pat. No. 2,594,779 to Huffman discloses a crankcase cleaning device in which a spray nozzle is attached to a fitting which can be screwed into the drain plug opening when the spray nozzle is used. A suitable cleaning fluid is directed onto the surfaces of the crankcase and the oil pan to remove contaminants. The crankcase can then be prelubricated by spraying a suitable lubricating agent through the spray nozzle onto the newly cleaned surfaces. Once this is done, the nozzle device is removed. The spent cleaning fluid and residual prelubricating liquid are, then, allowed to drain from the oil pan through the drain plug opening. As with the Stevens and Broadwell references, the device disclosed in Huffman lacks the ability to completely and safely remove residual contaminants remaining in the lube oil flow passages and on the surfaces of the oil flow engine components and also lacks a method for rapid efficient oil change.
The Huffman reference appreciates the dangers inherent in operating an engine without sufficient prelubricating fluid on its components. However like all the references, it fails to appreciate the volume of the empty new oil filter which must be filled with circulating fresh oil before any of the fresh oil reaches the parts which require lubrication.
In all oil change operations, including that disclosed in Huffman, when the new empty filter is installed, a time period exists in which engine oil is not reaching the moving components of the engine. Once the engine is started, the oil pump which circulates lubricating oil throughout the engine, must first fill the empty new filter. It must then fill the lube oil distribution passages. It is only after these volumes have been filled that fresh oil comes in contact with the engine parts requiring lubrication. It has been noted in the industry that most engine wear occurs in the first few seconds of engine operation due to he absence of lubrication film on the engine parts while the new empty engine oil is being filled by the engine oil pump.
U.S. Pat. No. 1,886,098 to Hedglon discloses an oil change system which is particularly adapted to stationary engines. The device disclosed in Hedglon includes a drain pipe permanently disposed in the drain opening of the engine. The drain pipe is permanently connected to suitable storage reservoirs and waste storage reservoirs by means of a suitable pipe. All lubricating and flushing fluids enter and leave the crankcase and oil pan by way of the drain pipe. This configuration makes it extremely difficult to contact remote regions of the crankcase with flushing fluid or introduced lubricating oil. Additionally, the system does not provide a means whereby introduced flushing fluid can be filtered and recirculated. Finally the Hedglon reference is silent about handling and disposal of the engine oil filter.
As can be appreciated, none of these devices present an integrated and efficient method for cleaning and lubricating the various recessed surfaces such as lube oil passages of the crankcase and oil pan and changing the engine oil at high speed. Furthermore none of these methods present a ready, easily implemented solution to the problem of oil filter removal and replacement. The previously known processes implicitly assume that the oil-laden filter will be discarded and a dry filter reinserted in its place. This process is wasteful and exposes the engine components to unnecessary wear during initial stages of engine operation, particularly after an oil change and filter replacement while the new oil filter and lube oil distribution passages refill with fresh oil.
Thus, it would be desirable to provide a process which accelerates removal of spent oil, associated contaminants, and degraded oil additives to permit eventual replacement with fresh engine oil in an essentially clean container in a unified process at one single location in an associated vehicle. It is also desirable to provide a method and device by which an oil change or oil change and crankcase components flushing operation can be accomplished which also eliminates the amount of spent and fresh oil handling and exposure. Finally it is desirable to provide a process which could easily be employed by the vehicle owner with all the benefits of the method of the present invention such as time saving, convenience, no spills, cleaner oil pans and engine components parts, with a minimum or no exposure to motor oil and, finally, longer lasting engines.